Many technician and secretary jobs require a lot of analytical knowlage in the medical field.
The mother is trying her best to convince her daughter. I think the mother is acting fine.
THRZ - Target Heart Rate Zone
It is the level of intensity of cardio during cardio exercise and has different ranges. 60% to 70% ,low intensity this is a warm up for beginners. 70%-80% moderate intensity, it is in this zone that improves body's ability to transport oxygen throughout the body and conditioning one's heart.80% - 90% it in this zone also that allows us to burn more calories.